#ifndef __M_FMT_H__
#define __M_FMT_H__

#include "level.hpp"
#include "message.hpp"
#include <vector>
#include <ctime>
#include <cassert>
#include <sstream>

namespace log
{
    // 抽象格式化基类
    class FormatItem
    {
    public:
        using ptr = std::shared_ptr<FormatItem>;
        virtual void format(std::ostream &out, LogMsg &msg) = 0;
    };
    // 派生格式化子类 -- 消息，等级，文件名，行号，线程id，日志器名，制表符，换行，其他
    class MsgFormatItem : public FormatItem
    {
    public:
        void format(std::ostream &out, LogMsg &msg) override
        {
            out << msg._payload;
        }
    };
    class LevelFormatItem : public FormatItem
    {
    public:
        void format(std::ostream &out, LogMsg &msg) override
        {
            out << LogLevel::toString(msg._level);
        }
    };
    class TimeFormatItem : public FormatItem
    {
    public:
        TimeFormatItem(const std::string &fmt = "%H:%M%S") : _time_fmt(fmt) {}
        void format(std::ostream &out, LogMsg &msg) override
        {
            struct tm t;
            localtime_r(&msg._ctime, &t);
            char tmp[32] = {0};
            strftime(tmp, 31, _time_fmt.c_str(), &t);
            out << tmp;
        }

    private:
        std::string _time_fmt;
    };

    class FileFormatItem : public FormatItem
    {
    public:
        void format(std::ostream &out, LogMsg &msg) override
        {
            out << msg._file;
        }
    };
    class LineFormatItem : public FormatItem
    {
    public:
        void format(std::ostream &out, LogMsg &msg) override
        {
            out << msg._line;
        }
    };
    class ThreadFormatItem : public FormatItem
    {
    public:
        void format(std::ostream &out, LogMsg &msg) override
        {
            out << msg._tid;
        }
    };
    class LoggerFormatItem : public FormatItem
    {
    public:
        void format(std::ostream &out, LogMsg &msg) override
        {
            out << msg._logger;
        }
    };
    class TabFormatItem : public FormatItem
    {
    public:
        void format(std::ostream &out, LogMsg &msg) override
        {
            out << "\t";
        }
    };
    class NLineFormatItem : public FormatItem
    {
    public:
        void format(std::ostream &out, LogMsg &msg) override
        {
            out << "\n";
        }
    };
    class OtherFormatItem : public FormatItem
    {
    public:
        OtherFormatItem(const std::string &str) : _str(str) {}
        void format(std::ostream &out, LogMsg &msg) override
        {
            out << _str;
        }

    private:
        std::string _str;
    };

    class Formatter : public FormatItem
    {
    public:
        Formatter(const std::string &pattern = "[%d{%H:%M:%S}][%t][%c][%f:%l][%p]%T%m%n")
            : _pattern(pattern)
        {
            assert(parsePattern());
        }
        // 对msg进行格式化
        void format(std::ostream &out, LogMsg &msg)
        {
            for (auto &item : _item)
            {
                item->format(out, msg);
            }
        }
        std::string format(LogMsg &msg)
        {
            std::stringstream ss;
            format(ss, msg);
            return ss.str();
        }

    private:
        // 对格式化规则字符进行解析
        bool parsePattern(){
            //1.对格式化规则字符串进行解析
            //abcd[%d{%H:%M:%S}][%t][%c][%f:%l][%p]%T%m%n]
            std::vector<std::pair<std::string, std::string>> fmt_order;
            size_t pos = 0;
            std::string key, val;
            while(pos<_pattern.size()){
                //1.处理原始字符串--判断是否是%,不是就是原始字符
                if(_pattern[pos] != '%'){
                    val.push_back(_pattern[pos++]);
                    continue;
                }
                //2.走到这说明是%，但是要判断是不是%%组成的原始字符
                if(pos+1 < _pattern.size() && _pattern[pos+1] == '%'){
                    val.push_back('%'); pos += 2; continue; 
                }
                //此时代表原始字符串处理完毕
               if(!val.empty()){
                    fmt_order.push_back(std::make_pair("", val));
                    val.clear();
               }

                //代表%后是一个格式化字符
                pos += 1;
                if(pos == _pattern.size()){
                    std::cout << "%之后没有对应的格式化字符！\n";
                    return false;
                }
                key = _pattern[pos];
                //还需要判断时候还有子格式 %d{%H:%M:%S}
                pos += 1;
                if(pos < _pattern.size() &&  _pattern[pos] == '{'){
                    pos += 1;
                    while(pos < _pattern.size() && _pattern[pos] != '}'){
                        val.push_back(_pattern[pos++]);
                    }
                    //走到末尾跳出了循环
                    if(pos == _pattern.size()) {
                        std::cout << "子规则{}匹配出错!\n";
                        return false; //没有找到匹配的'}'
                    }
                    pos += 1;
                }
                fmt_order.push_back(std::make_pair(key, val));
                key.clear();
                val.clear();
            }
            //2.根据解析得到数据初始化子项数组成员
            for(auto& it : fmt_order){
                _item.push_back(createItem(it.first, it.second));
            }
            return true;
        }
        // 根据不同的格式化字符创建不同的格式化子项对象
        FormatItem::ptr createItem(const std::string &key, const std::string &val){
            if(key == "d") return std::make_shared<TimeFormatItem>(val);
            if(key == "t") return std::make_shared<ThreadFormatItem>();
            if(key == "c") return std::make_shared<LoggerFormatItem>();
            if(key == "f") return std::make_shared<FileFormatItem>();
            if(key == "l") return std::make_shared<LineFormatItem>();
            if(key == "p") return std::make_shared<LevelFormatItem>();
            if(key == "T") return std::make_shared<TabFormatItem>();
            if(key == "m") return std::make_shared<MsgFormatItem>();
            if(key == "n") return std::make_shared<NLineFormatItem>();
            if(key == "") return std::make_shared<OtherFormatItem>(val);
            std::cout << "没有对应的格式化字符：%" << key << std::endl;
            abort();
            return FormatItem::ptr();
        }

    private:
        std::string _pattern; // 格式化规则字符串
        std::vector<FormatItem::ptr> _item;
    };
}

#endif